know-it-alls

noun

Definition of know-it-allsnext
plural of know-it-all
as in wiseacres
informal + disapproving a person who talks and behaves like someone who knows everything My neighbor is a real know-it-all, always telling me what to do.

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know-it-all
know-it-alls
knowledge
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“Know-it-alls.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/know-it-alls. Accessed 10 Sep. 2025.

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